What is multiple sclerosis (MS)?

Dr. Jeanne Morrison, PhD
Family Practitioner

Multiple sclerosis (MS) is a disease that affects the nervous system, which includes the spinal cord, optic nerves, and brain. In a healthy body, those nerves are surrounded by a protective layer of fatty tissue called the myelin sheath. If you have MS, that fatty layer is irreversibly damaged by an unknown cause. This makes it harder for your nerves to transmit impulses between your brain, eyes, and spinal cord, causing a range of symptoms.

There are four types of MS: Relapsing-Remitting MS, Primary-Progressive MS, Secondary-Progressive MS and Progressive Relapsing MS. Unless very severe, the condition is not life threatening, but it can be disabling. Currently, there is no cure.

Dr. Charles R. Smith, MD

Multiple Sclerosis targets the central nervous center and is presumed to be an auto immune disorder. In this video, Charles Smith, MD, explains what we know about the disease and what we don't.

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system where communication between the brain and other parts of the body is disrupted due to a break down in the insulating myelin that surrounds a person's nerves. The manifestation of this disease for each individual is different, depending upon where the damage occurs in the individual's central nervous system, and how extensive the damage is.

Common symptoms include fatigue, weakness of arms and legs, numbness, lack of coordination, loss of balance, visual problems, loss of bladder or bowel control, depression and emotional changes, cognitive problems and difficulty speaking. MS is not contagious or fatal, but a small number of people have a severe type of MS that may shorten life expectancy.

Brooke Randolph
Marriage & Family Therapy Specialist

Although multiple sclerosis (MS) can be understood as a neurodegenerative disorder, it is defined as an autoimmune disorder because the immune systems of sufferers attack their own central nervous systems, damaging the myelin sheath of neurons. This damage causes miscommunication and missed messages between the brain and the nerves. MS can be a very emotionally heavy diagnosis because it is chronic, there is no known cure, and it is a very unpredictable disorder. MS can affect any function controlled by the central nervous system.

Symptoms tend to come episodically without any warning. One day a person with MS may be functioning just fine and the next muscle weakness may inhibit walking. These symptoms can also terminate without any warning. The unpredictable nature can be very stressful, the lack of a cure can be disheartening, and the often degenerative nature of the disorder can be depressing.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Multiple Sclerosis: One of the most compelling findings of late is Epstein-Barr virus’ (EBV's) role in the autoimmune disease multiple sclerosis (MS). People with MS have a faulty immune response that causes immune cells to mistakenly attack the protective insulation (myelin) surrounding nerve fibers. When the myelin sheath is stripped it interferes with the transmission of nerve messages throughout the body and brain causing a wide range of neurological problems depending on where the damage occurs.

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Multiple sclerosis (MS) is an immune-mediated disorder of the central nervous system (optic nerves/brain/spinal cord). The cause (or causes) of MS is still not known, but it is felt to likely be an interplay between genetic and environmental factors.

Most people with MS are diagnosed between the ages of 20 and 50. It is more common among Caucasians of northern European ancestry, and it affects women significantly more than men. There are different forms of MS, but the majority of patients have relapsing-remitting MS, which means they will have episodes of symptoms (relapses) lasting days to weeks, then a return to a health baseline or close to baseline. People with MS can have many different neurological symptoms, including weakness, difficulty walking, sensory symptoms and cognitive issues.

Multiple sclerosis (MS) is a chronic disease in which the body's immune system attacks the myelin, the fatty sheath covering and insulating the nerve fibers that carry signals from the brain to other parts of the body. As a result of this, scar tissue called sclerotic plaques form, and the nerve fibers themselves may also be damaged. Nerve signals traveling through these damaged areas are distorted or interrupted, and this faulty transmission produces the variety of symptoms people with MS experience. Multiple sclerosis is one of the most common disorders of the central nervous system in younger adults, and affects three times as many women as men.

The course of MS—its progression, severity, and specific symptoms—varies greatly from patient to patient. Most patients (85 percent) initially have a relapsing-remitting form of the disease in which patients experience relapses (also called attacks or exacerbations) interspersed with periods of remission from the disease. During a relapse patients may have symptoms including blurred or double vision, weakness, numbness, tingling, balance problems, or dizziness. In many people these symptoms do not resolve completely when a relapse concludes. When MS is untreated, by fifteen to 20 years after diagnosis about 60 percent of people with relapsing-remitting MS have entered a phase of the disease called secondary progressive MS. During this phase many people experience no remission from the disease, while in some the disease plateaus. Disabilities accumulate in this form of MS, but not necessarily more rapidly than in relapsing-remitting MS.

About 15 percent of people with multiple sclerosis are diagnosed with primary progressive MS, which is characterized by a gradual decline in functioning in the absence of exacerbations or remissions.

Multiple sclerosis (MS) is a chronic condition in which the body’s immune system disrupts nerve function. The disease causes deterioration and permanent damage of the myelin sheath. The myelin sheath covers an axon on the nerve cell that sends signals throughout the body. When the signal is disrupted and healthy nerves are damaged, the body suffers many unwanted effects. Symptoms include fatigue, lack of coordination or balance, weakness, numbness, tingling, slurred speech, vision problems and tremors. (This answer provided for NATA by the Southern Connecticut State University Athletic Training Education Program)

Dr. Michael T. Murray, ND
Naturopathic Medicine Specialist

Multiple sclerosis (MS) is a syndrome of progressive nerve disturbances that usually occurs early in adult life. It is caused by gradual loss of the myelin sheath that surrounds the nerve cell. This process is called demyelination. One of the key functions of the myelin sheath is to facilitate the transmission of the nerve impulse. Without the myelin sheath, nerve function is lost. Symptoms correspond to the nerves that have lost their myelin sheaths.

Encyclopedia of Healing Foods

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Encyclopedia of Healing Foods

From the bestselling authors of The Encyclopedia of Natural Medicine, the most comprehensive and practical guide available to the nutritional benefits and medicinal properties of virtually everything...

Multiple sclerosis (MS) is a disease of the central nervous system (CNS), which is made up of the brain and spinal cord.

In MS, the nerves in the CNS get damaged. The immune system attacks the myelin protecting the nerves in the CNS. When the myelin is damaged, messages can’t be delivered properly through the damaged nerves. Sometimes the messages get lost completely. When this happens, the brain may have difficulty sending messages to the body. The brain may have trouble receiving messages too.

Multiple sclerosis (MS) is an inflammatory disease in which the body’s own immune system attacks the central nervous system, damaging the myelin — the covering, or insulation, of certain nerves in the body.

Although the cause of multiple sclerosis is unknown, the disease tends to strike adults 18 to 40 years of age. It can affect any part of the central nervous system, including the brain, spinal cord, and the nerves leading to the eyes. Multiple sclerosis can cause a wide range of disabilities, from mobility problems to cognitive deficits. The disease can exact a heavy emotional toll on those with multiple sclerosis and their loved ones.

Fortunately, multiple sclerosis has become a highly manageable disease over the past two decades. Although there is no cure, new therapies are available that can lessen the effects of multiple sclerosis and dramatically improve patients' quality of life.

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system that is characterized by an attack on myelin, the tissue that protects the brain’s nerve fibers. This interferes with the nerves’ ability to send signals to and from the brain and can result in symptoms such as difficulty with balance and memory.

Multiple sclerosis (MS) is a disease of the nervous system.
  • It affects the brain, eyes and spinal cord.
  • Symptoms depend on which parts of the nervous system are involved.
Each person has different symptoms that require a different course of treatment.
  • Multiple sclerosis refers to "multiple" areas hardening of the brain; "sclerosis" means hardening in Greek.
Multiple sclerosis causes scars in the brain that result in areas of hardening.
  • These scars occur when the body's immune system attacks the brain.
  • When cells from the immune system rush into an area it is called inflammation.
  • Inflammation damages the brain and results in symptoms.
Multiple sclerosis symptoms depend on what area of the brain is inflamed.
  • Immune system cells leave as the inflammation subsides.
  • Decreased inflammation improves symptoms, but brain damage remains.
  • Nervous system repairs may not be complete and symptoms may remain.
Multiple sclerosis attacks may recur, leading to more damage and possible disability.
  • Symptoms depend on what parts of the brain, spinal cord or eyes are damaged.
  • The time course of symptoms varies, depending on how often attacks occur.
  • Symptoms range from no symptoms to severe disability.
Multiple sclerosis research has led to effective treatments.
  • Decrease attacks and lessen disability.

Multiple sclerosis (MS) is the most common cause of nontraumatic disability in young adults in the United States today. It can lead to significant physical, cognitive and emotional impairment. MS is known to affect both the covering of nerves (myelin) as well as the nerves (axons) themselves in the brain and the spinal cord, and it is now known that this damage is mediated by both inflammatory and degenerative processes. It is suspected that MS occurs when a genetically susceptible person is exposed to an environmental trigger.

Multiple sclerosis (MS) is a chronic, sometimes disabling, disease of the central nervous system.

It is believed that MS is an autoimmune disease. In MS, the immune system—for reasons not understood—attacks and destroys myelin and the oligodendrocytes (oligo, few; dendro, branches; cytes, cells) that produce it. Though the body usually sends in immune cells to fight off bacteria and viruses, in MS they misguidedly attack the body's own healthy nervous system, thus the term autoimmune disease.

In multiple sclerosis, these misdirected immune cells (certain types of lymphocytes, T-cells, B-cells and natural killer cells) attack and consume myelin, damaging the myelin sheath—the fatty insulation surrounding nerve cells in the brain and spinal cord. Myelin acts like the rubber insulation found in an electric cable and facilitates the smooth transmission of high-speed messages between the brain and the spinal cord and the rest of the body. As areas of myelin are affected, messages are not sent efficiently or they never reach their destination.

Eventually, there is a buildup of scar tissue (sclerosis) in multiple places where myelin has been lost; hence the disease's name: multiple sclerosis. These plaques or scarred areas, which only are a fraction of an inch in diameter, can interfere with signal transmission. The underlying nerve also may be damaged, further worsening symptoms and reducing the degree of recovery.

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Dr. Louis Rosner

Multiple sclerosis (MS) is a disease that strikes only the central nervous system, which consists of the brain and spinal cord. These organs control the movements and functions of the entire body. As the brain sends and receives signals, the spinal cord funnels them in and out, to and from different parts of the body through a network of nerves.

The nerves are surrounded by insulating matter called myelin—a soft, white, fatty substance that forms a protective sheath for the nerves. The myelin sheath, which develops in the first ten years of life, insulates the nerve fibers and helps conduct signals through the body.

Multiple sclerosis is a disease where the myelin breaks down and is replaced by scar tissue. This demyelination can slow down or even block the flow of signals to and from the central nervous system to the rest of the body, impairing such functions as vision, strength or coordination. One important characteristic of myelin, however, is that it can repair itself. This ability, called remyelination, is one of the reasons MS is usually associated with many attacks, or exacerbations, and recoveries or remissions.

Multiple Sclerosis

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Too often, multiple sclerosis is thought of only as "the crippler of young adults." But in fact, 75 percent of all people with MS will never need a wheelchair. In Multiple Sclerosis, Dr. Louis J....

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.